Oh yes, the dreaded gap with the passenger side carpet. My Mystique has this too. The dealership after several times of complaints took the carpet and pulled it as far to that side as they could then installed clips or carpet rivets where you can not see them to hold it in place. Seems to work... but if you step into the car in just the right spot, it pulls out slightly. Problem is they cut the carpet too short...
Yes, this is a pain in the ass!!!
Eurythmian